Lineshapes of collision-induced absorption (CIA) and of collision-induced scattering (CIS) for monatomic gas mixtures of Ne-Ar

Abstract

Quantum mechanical lineshapes of collision-induced absorption (CIA) at different temperatures and of collision-induced light scattering (CIS) at room temperature are computed for gaseous binary mixtures of neon with argon using theoretical induced dipole moment and pair-polarizability trace and anisotropy as input. Comparison with measured spectra of isotropic and anisotropic light scattering shows satisfactory agreement, for which the uncertainty in measurement of its spectral moments is seen to be large. Empirical models of the dipole moment and pair-polarizability trace and anisotropy which reproduce the experimental spectra and the first three spectral moments more closely than the fundamental theory are also given. Good agreement between computed and experinental lineshapes of both absorption and scattering is obtained when potential models constructed from the thermophysical, transport and spectroscopic properties are used.

Keywords:

• pair polarizability trace
• anisotropy and dipole moment models/neon–argon

Acknowledgments

I am very grateful to Dr J. Borysow, Dr L. Frommhold and Dr G. Birnbaum for making available their published Fortran code with the different results of the collision induced absorption (CIA) for different systems.